Lamp-locking device.



J. G. MANLEY, J. THULIN & P. J. SMITH. LAMP LOCKING DEVICE.

APPLICATION FILED 13120.14, 1911.

1,040,366. Patented 0ct.8,1912.

a y' a UNITED STATES PATENT OFFICE.

JOHN C. MANLEY, JOHN THULIN, AND PETER J. SMITH, OF CHICAGO, ILLINOIS, AS-

SIGNORS 'I'O INVENTORS DEVELOPMENT-C0,, OF CHICAGO, ILLINOIS.

LAMP-LOCKING DEVICE.

Specification of Letters Patent.

Patented Oct. 8, 19-12.

To all whom it may concern:

Be itknown that we, JOHN C. MANLEY, JOHN THULIN, and PETER J. SMITH, citizens of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain-new and useful Improvement in Lamp-Locking Devices, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to lamp locking devices and has for its object the provision of an improved locking device for preventing the unauthorized withdrawal of articles such as incandescent 'u-lamp globes from their sockets.

In application Serial. #555,083, filed April 12, 1910, is set forth a lamp locking device broadly disclosing a device of this character in which means are set forth to indent the thin metal shell of the lamp in order to prevent such unauthorized withdrawal of a lamp.

In the present application We set forth new and improved means for accomplishing this indenting feature, which means may in a simple manner be attached to the present ordinary form of incandescent lamp sockets.

More particularly our invention in one of its embodiments provides a support, protruding from the socket, which support carries the indenting member. This indenting member is designed to project through the inner screw threaded metallic shell of the socket and to engage the thin metal shell of the lamp proper.

The indenting member is designed for actuation by means of a key. so that only authorized persons may operate this locking device to remove the lamp from the socket. We will describe our inventiommore in detail by reference to the accompanying drawing, in which:

Figure 1 is a side view partially in section of a socket provided with our improved locking device in association with a lamp; Fig. 2 is an enlarged view more clearly to illustrate the elements set forth in Fig. 1, and Fig. 3 is an enlarged side view of a portion of the socket and associated locking device.

Referring to Fig. 1, a socket 1 is shown having the ordinary operating device 2 and a lamp 3 having the screw threaded shell 4:

in association with said socket. The socket 1 has the customary lower metallic shell 5. In order to hold'the lamp 3 within the socket 1 an indenting member 6 is provided whose general outline is shown more clearly in Fig. 2, which indenting member has a protruding engaging'portion 7 and a key operated extension 8. The socket 1 has the customary screw threaded shell 9 on its interior and an insulating shell 10 is provided between the elements 9 and 5. The indenting member 6 is screw threaded and is carried by and operated within an insulating bushing 11. This insulating bushing is carried within a hood 12 preferably cylindrical throughout the major-portion of its length and having an outturned flange 13 at one extremity and an in-turned annular flange 14 at its opposite extremity. By means of the outturned flange 13 the hood 12 is fastened to the metallic portion 5 of the socket 1 by means of rivets 15, 15. The screw threaded shell 9 of the socket has a hole 16 through which the element 6 may pass and a corresponding hole 17 is providedin the in sulated shell 10. The indenting member 8 may'thus pass through the holes 16 and 17 when it is actuated by means of a key 18 and engage the screw threaded portion 4 of the lamp 3. The key 18 of course is made in such a way as to cooperate with the cooperating portion 8 of the element 6 of whatever form that may most desirablymeet therequirements.

It will be seen that when the indenting member 6 is screwed against the, screw threaded element 4 of the lamp3 that the screwthreaded element 4 is indented at 19 as most clearly set forth in Fig. 2 where a portion of the shell 4 is broken away to reveal this indentation. It will be seen by thus indenting the lamp it cannot be removcdfrom the socket without destroying the entire structure, or else having a key arranged to fit the key portion 8 of the member 6. Holes 20, 20 are provided in the hood 12 so 'that'the locking devices-may be sealed in any of the well known ways, for instance, by,putting a wire through the holesand providing an ordinary lead seal for the ends thereof.

The importance of the device will be more apparent when it is taken into account that the present day lamps of the tungsten variety are very expensive and are the source of much unauthorized removal.

It will of course be apparent that changes may be made in the device herein disclosed without departing from the broad features of the invention herein, and the specific description given above of the particular form set forth herein is not intended to limit the invention to this particular form. Having, however, thus described one embodiment of our invention, we claim as new and desire to secure by Letters Patent the following:

1. A lamp socket having means to prevent the unauthorized withdrawal of a lamp having a thin metal band adapted for association with said socket, said means includ ing an indenting member adapted to occupy the indentation made by it in the lamp band, an insulating support for said member with which said member has screw threaded engagement, and a hood fastened to the socket for holding said insulating support.

2. A lamp socket having means to prevent the unauthorized withdrawal of a lamp having a thin metal band adapted for association with said socket, said means including an indenting member adapted to occupy the indentation made by it in the lamp band, an insulating support forsaid member with which said member has screw threaded engagement, and a hood fastened to the socket for holding .said insulating support, said indenting member having key controlled operating means.

3. A lamp socket having meaus to prevent the unauthorized withdrawal of a lamp having a thin metal band adapted for association with said socket, said means including an indenting member adapted to occupy the indentation made by it in the lamp band, an insulating support or said member with which said member has screw threaded engagement, and a hood fastened to the socketfor holding said'insulatingsupport, said indenting member having key controlled operating means, said socket having an inner screw threaded shell provided with an aperture to accommodate said indenting member.

4. A lamp socket having means to preventthe unauthorized withdrawal of a lamp having a thin metal band adapted for association with said socket, said means including an indenting member adapted to occupy the indentation made by it in the lamp shell, an insulating support'for said member with which said member has screw threaded engagement, a metallic shell fastened to the socket for holding said insulating support, and means on said shell to prevent withdrawal of said insulating material.

In witness whereof, we hereunto subscribe our names this 8th day of December A. 1)., 1911.

JOHN C. MANLEY. JOHN. THULIN. PETER J. SMITH. Witnesses:

O, M. WERMIQH, HAZEL Jones. 

